Obtaining all the nutrients we need through our diet is much more challenging now than it was 50 years ago. We strive to make the right choices when presented with the freshest organic vegetables for example, but with high organic prices, limited stock availability coupled with long storage times, do we actually get what we believe we are supposed to be getting? Or do we just turn a blind eye to food quality and eat our veggies without a regard to how it’s produced?

In 2000, 'Organic Magazine' compared nutrient values of foods as listed by the USDA in 2000 with those listed in 1963. Here is a sample of the decline they found:

In a cross section of vegetables, including Beets, Spinach, Corn and Collards, Vitamin C declined an average 50%, Magnesium declined 15-80% and Potassium declined 10-40%.

In Anne-Marie Mayes’ British study in 1997 called “Historical Changes in the Mineral Content of Fruits and Vegetables”, she identified that there are “statistically significant reductions in the levels of Calcium, Magnesium, Copper, and sodium in vegetables and of Magnesium, Iron, Copper and Potassium in fruit.”

This is troubling news for people who are trying to eat a balanced diet. Even healthy foods, like fresh fruits and vegetables, may not be as healthy as they once were.

Who is to blame?

The majority of farmers in the western world have dramatically changed their farming practices in the last 40 years, and use crop varieties which achieve higher yields and economic gains, but without the nutritional gains. As a result our food contains fewer nutrients when they come out of the soil, and when they are processed these nutrients are further depleted. The organic movement is trying to redress the balance, however as its production accounts for only 10-15% of the total market supply, the majority of us need to be reassured about the conventional methods of farming.

Specific Reasons for Nutrient depletion in fruits and vegetables include:

Depletion of organic matter in the soil. Famers traditionally have use organic fertilizers which replenishes the soil with humus, the vital ingredient needed to make minerals locked deep in the soil available. As farmers have moved towards more intensive methods of farming, inorganic, petroleum-based, fertilizers are used, like Nitrogen, Potassium and Phosphorus. These deplete the soils of humus and thus decrease overall fertility long term.

Depletion of minerals due to over-fertilising of Nitrogen Phosphorus and Potassium. Soil needs time to reconstitute itself, and new food production techniques with emphasis on output give it no time to recover its health. There is no provision to make up for the wide range depleted minerals in the soil as a result of intensive crop production. Only Nitrogen, Phosphorus and Potassium chemical fertilizers are used to replenish soils. These fertilizers are highly acidic and disrupt the pH (acid/alkaline) balance of the soil making other minerals unavailable to the plant and so the plant grows deficient in vital trace minerals like zinc, iron, magnesium and copper.

Desire for Better-looking Food. In 1997, Organics Centre published a report titled "Still No Free Lunch: Nutrient levels in U.S. food supply eroded by pursuit of high yields”. The report found clear evidence that as the produce we eat gets larger in size, its vitamins, minerals and beneficial chemical compounds diminish, as do taste and aroma. The additional undesirable trade-off of bigger apples and golden ears of corn is the lower nutritional value of the entire produce.

Preferences for Exotic varieties. People are turning to more exotic varieties and out-of-season imports such as courgettes, corn on the cob, and frozen exotic vegetables, such as mange-tout and bean-sprouts. There are many reasons to believe that locally grown food (foods produced within 100 miles of your homes) might be better for you than produce purchased in the supermarket. Being in transit or cold-stored for days affects not only the taste of your food, but also the nutritional value of the food declines.

Reliance on Convenience Foods. Diet patterns of families are changing and refined foods are consumed in such amounts that intake of minerals and vitamin-rich foods is far lower than it should be. The magnesium content of refined foods is usually very low. Deficiencies in Magnesium and other essential minerals are commonly seen in those who eat a diet high in processed-foods and those who cook or boil all their foods, especially their vegetables. Refining and processing of grains and other foodstuffs typically results in a loss of 70% or more of the natural magnesium content of the food, as well as other vital nutrients. The conversion of wheat into flour results in a loss of 82% of magnesium. Refining rice into polished rice sacrifices 83% of its magnesium.

Why should we care?

As early as the 1930’s, scientists warned that declining nutrient levels of our food would lead to a rise in chronic degenerative diseases like heart disease, cancer and adult-onset diabetes. In 1996, the Uniform Data Standards Committee (UDSC) released a study that correlated a decrease in minerals in food to health issues prevalent today. (See Table 3)

Life Clinic Says:

Hong Kong imports nearly all its foods, some of which are shipped from a long distance taking many hours to get here. Very little studies have been demonstrated on the effects of the produce imported, however taking into account the previous studies cited above it appears we could be more deficient in nutrients than first thought.

Here’s what we can do:

Choose organic food. Organic farmers let soil reconstitute itself before planting and use organic manures so there is a possibility that the soil they use has the right chemical composition, hence their produce is likely to be more nutritious.

Eat Locally-grown food Eating food grown locally in Hong Kong ensures that they are as fresh as possible, and less likely to be depleted of nutrients from long transit times. When looking for choices we recommend homegrownfoods – website www.homegrownfoods.com.hk

Take vitamin and mineral supplements. The bioavailability of nutrients in supplements is 80-100% if the right supplements are selected. Compared to foods, which is unpredictable, this is an assured way to cover any potential deficiencies and provide our basic requirements. Choose a supplement that is pharmaceutical-grade, and potency and purity tested by independent third parties. Using personalised supplementation, can help reduce the risk of chronic, degenerative diseases further.

If you would like more information please contact us, or call reception for enquiries on 2881 8131.